Life Orb and EVs make this awesome Pokemon hit pretty hard. Aftermath is for the dying damage, and since most Ground moves are Physical, they'll be taking some damage. Night Slash can crit, and Poison Jab can poison. Rock Smash is for those Steel types that are just laughing at me, and the Defense lowering is nice :D Toxic works well with this set, since the constant Defense drop can seriously tick people off, force a switch, and give this guy a chance to poison, making an even more annoying situation. Ragequit team anyone?

Skuntank@Black Sludge

Explanation

Surprisingly, Skuntank is able to learn Defog. With a unique typing different from most Defoggers, it can easily surprise several players.

Defog is used for hazard removal.
Taunt deals with hazard-setters and forces them to use an attacking move.
Sucker Punch has priority and STAB. This is useful because the taunted hazard-setters would have to use an attacking move, but Skuntank can beat them with Sucker Punch.
Protect is mainly used for scouting moves, but it isn't as good as Pursuit, which can catch the hazard-setters on the switch-out. Poison Jab can also be used in this slot for dual STABS.

Note: EVs are used to make Skuntank bulky, yet still have the necessary power.